1. Field of the Invention
The present invention relates generally to medical devices, systems and methods. In preferred embodiments, the present invention relates to methods and apparatuses for effecting lung volume reduction by aspirating isolated segments of lung tissue.
Chronic obstructive pulmonary disease is a significant medical problem affecting 16 million people or about 6% of the U.S. population. Specific diseases in this group include chronic bronchitis, asthmatic bronchitis, and emphysema. While a number of therapeutic interventions are used and have been proposed, none are completely effective, and chronic obstructive pulmonary disease remains the fourth most common cause of death in the United States. Thus, improved and alternative treatments and therapies would be of significant benefit.
Lung function in patients suffering from some forms of chronic obstructive pulmonary disease can be improved by reducing the effective lung volume, typically by resecting diseased portions of the lung. Resection of diseased portions of the lungs both promotes expansion of the non-diseased regions of the lung and decreases the portion of inhaled air which goes into the lungs but is unable to transfer oxygen to the blood. Lung reduction is conventionally performed in open chest or thoracoscopic procedures where the lung is resected, typically using stapling devices having integral cutting blades. Although these procedures appear to show improved patient outcomes and increased quality of life, the procedure has several major complications, namely air leaks, respiratory failure, pneumonia and death. Patients typically spend approximately 5-7 days in post-op recovery with the majority of this length of stay attributed to managing air leaks created by the mechanical resection of the lung tissue.
In an effort to reduce such risks and associated costs, minimally or non-invasive procedures have been developed. Endobronchial Volume Reduction (EVR) allows the physician to use a catheter-based system to reduce lung volumes. With the aid of fiberoptic visualization and specialty catheters, a physician can selectively collapse a segment or segments of the diseased lung. An occlusal device is then positioned within the lung segment to prevent the segment from reinflating. By creating areas of selective atelectasis or reducing the total lung volume, the physician can enhance the patient's breathing mechanics by creating more space inside the chest wall cavity for the more healthy segments to breath more efficiently.
Additional improvements to EVR are desired. A delivery system is desired which can position an occlusal device within a desired segment of a lung passageway with high accuracy. Such a delivery system should be easy to use, should allow interchangeability of a variety of instruments, and should allow delivery of multiple occlusal devices. It is desired that such delivery of multiple occlusal devices be achieved while maintaining evacuation of a diseased region of the lung. It is also desired to provide a system which utilizes conventional bronchoscopes to deliver the occlusal devices to the lung passageways. Such utilization should be easy to operate and should not interfere with additional therapies which utilize the bronchoscope. At least some of these objectives are met by the current invention.
2. Description of the Background Art
Patents and applications relating to lung access, diagnosis, and treatment include U.S. Pat. Nos. 6,709,401; 6,585,639; 6,527,761; 6,398,775; 6,287,290; 5,957,949; 5,840,064; 5,830,222; 5,752,921; 5,707,352; 5,682,880; 5,660,175; 5,653,231; 5,645,519; 5,642,730; 5,598,840; 5,499,625; 5,477,851; 5,361,753; 5,331,947; 5,309,903; 5,285,778; 5,146,916; 5,143,062; 5,056,529; 4,976,710; 4,955,375; 4,961,738; 4,958,932; 4,949,716; 4,896,941; 4,862,874; 4,850,371; 4,846,153; 4,819,664; 4,784,133; 4,742,819; 4,716,896; 4,567,882; 4,453,545; 4,468,216; 4,327,721; 4,327,720; 4,041,936; 3,913,568 3,866,599; 3,776,222; 3,677,262; 3,669,098; 3,542,026; 3,498,286; 3,322,126; WO 98/48706; WO 95/33506, and WO 92/10971.